dump-wii-games.md: Specifically run cmd for joining split Wii games (#181)

* Specifically run cmd for joining split wii games

docs/extras/dump-wii-games.md

@@ -47,9 +47,8 @@ If you intend to use this guide to share your dumped games, don't.
 #### Windows {docsify-ignore}
 
 1. Copy all the files that share the same name and end with `.partX.iso` in a folder on your computer.
-1. Open up a Command Prompt window.
-1. Use the `cd <path>` command and replace `<path>` by the path to your `.partX.iso` files.
-1. Use the following command as is: `copy /b *.part?.iso game.iso`.
+1. Right-click inside the folder while holding Shift and select `Open PowerShell Window Here`.
+1. In the PowerShell window, run the following command as is: `cmd.exe /c "copy /b *.part?.iso game.iso"`.
 
 #### macOS/Linux {docsify-ignore}